Our ability to attend and selectively process relevant stimuli in a cluttered visual scene is crucial in guiding appropriate behavior. Although recent work has begun to elucidate the underlying neural mechanisms of voluntary visual spatial attention, the neural basis of involuntary visual spatial attention remains elusive. Disorders of attention are commonly linked to mental health ailments that affect millions of patients, including schizophrenia, autism, and attention-deficit disorders. Thus, furthering our understanding of how involuntary attention operates in the brain will potentially mitigate some of the devastating effects that these mental health ailments bring. The overarching goal of the proposed research is to identify the neural mechanisms and correlates of involuntary attention, which we will address through two specific aims. First, we will determine whether V4 responses are selective for voluntary attention cues. We will record V4 responses to these stimuli and compare them to V4 responses to target stimuli that require selection via voluntary attention. In our second aim, we will determine whether this V4 selection is dependent on saccade planning. The monkey will fixate and then saccade to a relocated target. Meanwhile, we will record V4 responses to the same stimuli presented in aim 1. In this paradigm, however, the target stimuli will appear after the monkey has already begun planning an eye movement to a region of the visual field away from the V4 RF. We will determine whether saccade planning affects V4 selection for involuntary attention cues. While the results of the proposed research will provide insight into how involuntary attention is deployed in a healthy brain, they may also impact public health by elucidating the physiological basis of attention disorders in humans, which affect approximately 5% of children in the U.S. Additionally, these findings may further our understanding of visual-oculomotor coordination disorders, including dyslexia, which is estimated to affect 10% of U.S. citizens.